Bucket cleaner for excavating machine



Jan. 10, 1967 v, s, PENOTE ET AL 3,296,719

BUCKET CLEANER FOR EXCAVATING MACHINE Filed Aug. 8, 1963 5 Sheets-Sheet 1 m '1 H Fig. /4

f I /68 INVENTORS VINCENT s. PENOTE BY MELVIN K. REAR Jan. 10, 1967 v. s. PENOTE ET L BUCKET CLEANER FOR EXCAVATING MACHINE 5 Sheets-Sheet 2 Filed Aug. 8, 1965 INVENTORS VINCENT s. PENOTE BY MELVIN K.REAR

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ATTORNEYS Jan. 10, 1967 v. s. PENOTE E BUCKET CLEANER FOR EXCAVATING MACHINE 5 Sheets-Sheet Filed Aug. 8, 1965 INVENTORS ATTORNEYS H 11 I: i fi k T: if 1 Jan. 10, 1967 v, s, PENOTE ET AL 3,296,719

BUCKET CLEANER FOR EXCAVATING MACHINE INVENTORS VINCENT S. PENOTE MELVIN K. REAR ATTORNEYS Jan. 10, 1967 v, s, PENOTE ET AL 3,296,719

BUCKET CLEANER FOR EXCAVATING MACHINE Filed Aug. 8, 1963 5 SheetsSheet 5 Fig. /3

Fig. /7

INVENTORS VINCENT S. PENOTE BY MELVIN K. REAR AT TOR NEYS United States Patent f BUCKET CLEANER FOR EXCAVATENG MAQHINE Vincent S. Penote, Shaker Heights, and Melvin K. Rear,

Qhesterland, Ghio, assignors to The Cleveland Trencher Company, Cleveland, Ohio, a corporation of Ohio Filed Au". 8, 1963, Ser. No. 360,727 11 Claims. (Cl. 3797) This invention relates in general to a bucket cleaner for an excavating machine, and more particularly to a fluid operated bucket cleaner and associated control system, for insuring the removal of excavated material from the excavating buckets of an endless digging unit of an excavating or trenching machine.

In the United States Patent No. 2,730,821 issued January 17, 1956 to Frank J. Fetzner, there is disclosed a bucket cleaner of somewhat the general type of the instant application, and wherein the cleaner is pivoted to the boom of the excavating machine, and is adapted to have an active position in which the mechanism is effective for removing excavated material from the excavating buckets of the trenching machine, but which embodies latch means for releasing the cleaner for gravity-actuated, downward pivotal movement, when undue resistance is encountered in a bucket.

The present invention provides a cleaner which does not pivot on a fixed center point, but instead moves along a plurality of paths, facilitating the movement of the cleaner to an operative position and withdrawal thereof to an inoperative position, and wherein the cleaner is actuated by a fluid powered motor unit. When an obstruction, such as a rock or the like, comes up in a bucket during digging operations, the control system for the motor unit is so arranged that upon predetermined engagement of the obstruction by the cleaner, the system is automatically actuated to permit withdrawal of the cleaner from operative position, and allow the obstruction to pass beyond the cleaner, without damage to the latter or to the buckets. The control system is preferably adjustable so that various digging conditions can be compensated for, such as for instance when the machine is operating in very sticky, tenacious soil, or the easier to clean types of soil.

Accordingly, an object of the invention is to provide a novel bucket cleaner for an excavating or trenching machine.

Another object of the invention is to provide a fluid powered cleaning mechanism for a trenching machine in which the cleaning mechanism may be selectively and expeditiously moved into an operative position wherein it can clean soil from the excavating buckets of an excavating machine, and to an inoperative position wherein it is out of interfering relationship with other components of the excavating machine.

Another object of the invention is to provide a cleaning device for a trenching machine which does not pivot on a fixed center point, but instead slides or moves along a combination of paths, to cause the entire cleaner to pass through a portion of an arc of a circle, and in a manner which expedites the operation of the cleaning device on the trenching machine.

A more specific object of the invention is to provide an excavating bucket cleaner mechanism for a trenching machine wherein the cleaner mechanism comprises an arcuate-like arm or comb movably connected to a combination of two rail systems located on the trenching machine with one of the rail systems being generally linearly extending and the other rail system being arcuately extending, and wherein a hydraulic powered, double acting motor unit is provided coacting between the trenchdgfififllfl Patented Jan. 10, 1967 ing machine and the cleaning mechanism, for moving the cleaning mechanism along said rail systems to and from an active position.

A still further object of the invention is to provide a novel bucket cleaner for an excavating machine which is fluid powered and controlled, and which embodies a system for preventing damage to the cleaning unit in the event that an obstruction, such as a rock is lodged in a bucket and engages the cleaning device.

A further object of the invention is to provide a novel fluid actuating and control system for a cleaning mechanism of an excavating machine, and a system which includes an automatic, fluid actuated trip means, for protecting the cleaning mechanism and the excavating machine against obstructions which may be lodged in the buckets of the machine.

Other objects and advantages of the invention will be apparent from the following description taken in conjunction with the accompanying drawings wherein:

FIG. 1 is a fragmentary, partially sectioned, side elevational view of a rotary wheel-type trenching machine embodying the cleaning unit of the invention;

FIG. 2 is a fragmentary sectional view taken generally along the plane of line 22 of FIG. 1 looking in the direction of the arrows and illustrating in particular the rail structure sub-assembly for guiding the movement of the cleaner on the trenching machine;

FIG. 3 is an enlarged fragmentary top plan view of one of the connections of the bucket cleaner mechanism to one of the guide rails therefor;

FIG. 4 is an enlarged side elevational view of the rail structure sub-assembly, as discussed in connection with FIGS. 1 and 2;

FIG. 5 is an enlarged sectional view of the FIG. 4 rail structure taken for instance along the plane of line 55 of FIG. 4 looking in the direction of the arrows;

FIG. 6 is an enlarged side elevational view of the base portion of the cleaning device or arm of the invention, and with the fingers or comb of the device having been removed;

FIG. 7 is an elevational view of the FIG. 6 base taken from the right hand side thereof;

FIG. 8 is a fragmentary generally top plan view of the FIG. 6 base taken substantially along the plane of line 88 of FIG. 6 looking in the direction of the arrows;

FIG. 9 is a fragmentary elevational view of the FIG. 6 base taken generally along the plane of line 9-9 of FIG. 6 looking in the direction of the arrows;

FIG. 10 is a fragmentary bottom plan view of the FIG. 6 base taken generally along the plane of line 10-10 of FIG. 6, looking in the direction of the arrows;

FIG. 11 is an elevational view of the head or comb of the bucket cleaner, which head or comb is adapted for attachment to the base section shown in FIG. 6;

FIG. 12 is a side elevational view of the FIG. 11 comb;

FIG. 13 is a sectional view taken generally along the plane of line 1313 of FIG. 12 looking in the direction of the arrows;

FIG. 14 is a fragmentary, reduced size end elevational view showing the comb or head section of FIGS. 11 and 12, as mounted on the base section of FIGS. 6 and 7;

FIG. 15 is an enlarged, side elevational view of one of the brackets used to movably mount the cleaning device on the rail structure sub-assembly of FIG. 4;

FIG. 16 is an end elevational view of the FIG. 15 bracket taken from the left hand end thereof; and

FIG. 17 is a schematic illustration of a fluid system for use with the bucket cleaner mechanism, and one that embodies means for preventing damage to the cleaning mechanism and/ or to the buckets, in the event an obstruction is lodged in a bucket, and engages the cleaning device.

The present invention is especially adaptable for use in connection with a rotary wheel type of excavating machine, as shown for instance in the aforementioned US. Patent 2,730,821. As shown in FIG. 1, the digging unit of the excavating machine may be mounted adjacent the rear end of the excavating machine, and on an elongated boom frame 12 of generally conventional construction, for rotary movement in a generally vertical plane.

The digging unit It) may be of a conventional construction comprising a pair of laterally spaced annular rings 14 supported by rollers 16, which are carried by a carriage 16a, the details of which are well known in the art. The rings 14 may be connected together by a series of buckets 18 attached to the rings as by means of fasteners. The buckets may be of any suitable type, but are preferably of the well known generally arcuate configuration type, and are preferably provided with rooter teeth 20 mounted on the leading edges thereof in the conventional manner, for facilitating the digging operation by the buckets. The rear of the buckets may be provided with a plurality of laterally spaced fingers or tines 22, extending inwardly toward the rings 14, and forming what is known as a semiclosed back for the bucket. The tines 22 may be permanently secured to the rear edge of the respective bucket, or may be detachably secured thereto and mounted thereon by means of conventional socket portions.

The digging unit 10 may be rotated or driven in any suitable manner and preferably by means of a power unit such as an internal combustion engine, mounted on the forward end of the excavating machine, and suitably coupled in a known manner to the digging unit. A transversely extending conveyor mechanism 26 extending through the digging wheel, is preferably provided, mounted on the boom frame 12 and adapted to receive excavated material from the buckets of the digging unit and transfer it to a side of the digging unit. Conveyor unit 26 may be shiftable transversely of the boom and may be driven in either lengthwise direction, and in a manner known in the art.

Referring now in particular to FIGS. 1 through 12, in accordance with the invention there is provided a novel fluid powered bucket cleaning device 30 movably mounted on the digging unit boom 12 through a predetermined range, and including an active position as shown in full lines, wherein it is operable to scrape or remove material from the buckets, and from which it may be swung down to an inactive position B shown in phantom lines in FIG. 1, and vice versa. Such a cleaning device is adapted to be mounted upon a rail sub-assembly 32 (FIGS. 2 and 4) which guides and supports the bucket cleaner on the digging unit.

Such rail sub-assembly 32 comprises laterally spaced first rail members 34 which as best shown in FIG. 4 extend generally linearly and are each formed from a generally vertical web or flange 34a and the attached generally horizontally extending web or flange 34b. Attached to web 3412 of each rail member 34 are front and rear brackets 36 and 36a respectively. Brackets 36, 36a are adapted for attaching the respective rail member 34 of the sub-assembly to the boom frame of the excavating machine as will be hereinafter described in greater detail.

A generally rearwardly disposed, arcuate rail member 38 also forms a part of the rail sub-assembly, with such arcuate member 38 being of generally similar construction as aforementioned in connection with rail member 34, and comprising a laterally projecting arcuately curved web 38a and a generally vertically oriented web 38b. Rail 38 is connected as by welds to bracket 36 and an angular arm 40 may connect the rail members 34 and 38, for rigidifying such assembly.

Extending between the laterally disposed rail members 34 of the rail sub-assembly and attached thereto is a motor unit support member 42 (FIG. 2) which includes a generally depending bracket member 42a, which is adapted to pivotally connect one end of a fluid powered, reciprocal motor unit 44 (FIG. 1) the latter being adapted to extend between the cylinder support member 42 and the cleaner mechanism 30, and to actuate the cleaner mechanism from an active position to an inactive position and vice versa.

Rail sub-assembly 32 is suspended or coupled to the longitudinally extending beams 45 of the trenching machine boom 12 by means of bracket and spacer structure 46 (FIGS. 1 and 2) which is attached as by means of bolts 46a to the respective beam of the boom structure, and which may be attached as by means of fasteners to the associated of the brackets 36, 36a of the rail subassernbly. It will be seen, therefore, that the rail subassembly 32 is suspended or oriented intermediate the longitudinal beams 45 of the boom in a comparatively rigid manner.

The cleaning mechanism 30 may comprise a base member 50 (FIG. 6) which has a generally arcuate body portion 52a, and depending laterally spaced arm portions 52b. The other end of the aforementioned fluid powered motor unit 44 is adapted for pivotal coupling as at 54 to arm portions 52b of the base member 50. Base member 50 may be of fabricated construction and with the body portion 52a including an opening or passageway 55 extending therethrough, and through which the motor unit 44 extends. One end of body portion 52a includes apertured bracket structure 56 for detachably mounting the comb or finger unit 57 (FIGS. 11 and 12) of the cleaning mechanism. The other end 58 of the body portion 52a is apertured as at 58a for detachable connection to a pivot mounting 60 (FIG. 3) which pivot mounting supports mechanism 30 on rail sub-assembly 32.

Pivot mounting 69 includes trunnions 62 for journaling mounting 60 to laterally spaced brackets 64 which are in turn disposed in assembled relation with the respective of the aforementioned rail members 34 of rail sub-assembly 32. As best shown in FIGS. 15 and 16, the brackets 64 each has flanges or arms 64a thereon which partially encompass the vertical web 34a of the respective rail member 34, and mount the cleaner mechanism thereon.

Base member 51) is also provided with openings 66 (FIG. 6) through the side walls thereof, and which openings provide for journaling of brackets 64 (FIG. 1) to base 50. Brackets 64 may be generally similar to the aforementioned brackets 64 and may likewise embody flanges or arms which overlap vertically oriented flange or Web 38b of the respective arcuate rail 38, and movably attach the base member 50 to the rail sub-assembly 32. It will be seen, therefore, that upon actuation of the cleaning unit to an activated position wherein it projects intermediate the side rings 14 of the digging wheel and up into the associated buckets 13, that end 58 of the base member 50, while pivoting relative to its brackets 64, will move in a linear path along rails 34, while end 56 of the base member 56 will move in a generally arcuate path along rails 38.

Preferably detachably connected as by means of nuts and bolts, to the base member 50 of the cleaning unit is the aforementioned comb or finger assembly 57 (FIGS. 11 to 14). Finger assembly 57 may comprise a base flange or bracket 68 having openings 68a therein, which correspond to similar openings 69 in the base member end bracket 56 for attaching the comb to the base memher, and a plurality of fingers 70 of generally arcuate configuration projecting upwardly from bracket 68.

Fingers 70 may each comprise a bottom flange portion 70a (FIGS. 11 to 13) and a generally vertically oriented flange portion 70b, which reinforces the respective finger and gives it high strength characteristics. As seen in FIG. 13, flange 7% preferably possesses greater dimensions in both directions as compared to flange 700.. Pingers 70 may be provided with hardened tip members 72 for facilitating the cleaning operation and increasing the service life of the cleaning device. it will also be understood that such tip members are preferably detachably attached to the finger members, such as for instance by tack welds, so that such tip members can be periodically replaced as they wear without necessitating the replacement of the entire comb structure. As shown, each of the tines or fingers 70 is preferably provided with a somewhat oblique abutment section 74 spaced downwardly or inwardly from the tip, which abutment section is adapted for abutting engagement with soil being forced out of the respective bucket, to insure that the soil will drop down onto the conveyor mechanism 26 mounted on the boom. Abutments 74 also tend to break-up heavy types of soils and clays. It will be understood that the tines 22 on the buckets pass between the spaces between the fingers 76 of the comb and therefore there is no interference between such cleaner structure and the buckets upon rotation of the digging wheel.

As can be best seen in FIG. 1, the distal or cleaning end of the bucket cleaner is disposed at an angle of approximately with respect to the horizontal, in the raised or activated position of the bucket cleaner, which greatly facilitates the scraping of material out of the buckets, and places minimum stress on the bucket cleaner, as opposed to a bucket cleaner wherein the bucket cleaner would be oriented more perpendicularly up into the bucket.

It will be seen that the arrangement can be readily adapted for use with different widths of buckets or different widths or sizes of digging wheels, by merely providing the proper width of comb or finger structure on the base member, and with such an arrangement being applicable for use both on new excavating machines, and on existing excavating machines.

Referring now to FIG. 17 there is diagrammatically and schematically illustrated a fluid system which may be utilized for controlling the fluid powered motor unit 44 which actuates the bucket cleaner 30. In present day excavating machines, fluid control systems are sometimes provided for actuating and controlling various fluid powered or hydraulic motor units on the excavating machine, which in turn actuate and control various components of the excavating machine. One of the working components of an excavating machine which is sometimes actuated and controlled by hydraulic motor units in present day practice is the discharge conveyor of the machine in its shifting movement to various work positions, and for actuating the endless belt of the conveyor, for moving excavated material it receives from the digging unit of the machine, to a side of the excavation. Such fluid power system conventionally comprises a pump 76 (FIG. 17) preferably driven from the main power unit or internal combustion engine of the excavating machine, and attached by means of conventional fluid transmitting lines to the motor unit 44 and to a reservoir 77 mounted on the machine. The pump 76 is adapted to furnish pressurized fluid to a distributing valve member 78 which may be an open center valve, both work ports blocked, pressure returns to tank 77 through 8%, and which distributing valve may be of the conventional spring-loaded, axially movable spool type, for directing the fluid through a port 82 or a port 82a to the motor unit 44, with one of said ports being pressurized while the other of said ports returns the fluid to the reservoir. The system has at least one cross-over relief valve section 84 and 85 respectively, which relief sections are of conventional construction including adjustable control means for selectively changing the setting or pressure at which the respective relief valve will be actuated, thereby permitting oil to flow from one side or one line 36 to the other side or line 88 thereof, and vice versa. The system also preferably has a check valve 90 disposed in a bypass line 92 extending from reservoir around the distributing valve 78 to line 86 leading to the piston side of the motor unit 44. Relief valve sections 84, may be formed as integral parts of the distributing valve section proper 78 or directly connected thereto, or they may be separated from the distributing section 78 and located for instance adjacent to the motor unit 44. An advantage to the latter arrangement is a shorter hose length path from one end of the motor unit cylinder to the other end thereof, through the relief valve section.

Now in the event that an obstruction, such as a rock lodges in the bucket during the digging operation of the machine, and engages the fingers or comb 57 of the cleaning device, this pressure causes an overload on the cleaner mechanism. The pressure within the piston rod side 94 (FIG. 17) of the motor unit 44 thereby rises to a point above the adjustable setting of the relief valve section 85, causing actuation of such relief valve section, and passage of the fluid or oil from the piston rod side of the motor unit 44 through relief valve section 85 and line 86 to the piston side of the motor unit, thereby permitting extension of the piston rod of the motor unit and allowing the cleaner mechanism 30 to fall toward the interior of the digging wheel a suflicient distance to allow the obstruction to pass without doing damage to the cleaner mechanism and/ or to the buckets. The aforementioned external line 92 with a check valve therein makes it possible for sufl icient fluid to be drawn into the piston side 98 of the motor unit, as required to make up for the volumetric differential caused by the presence of the piston rod, and will aid in preventing cavitation. When the machine operator observes that the cleaning mechanism has dropped down from its normal operative position, he can raise it back into normal position by proper actuation of the spool of valve 78 to apply pressurized fluid to piston rod side 94 of the motor unit, thereby swinging the cleaning mechanism back up to the position illustrated in full lines in FIG. 1. The automatic dropping down of the cleaning mechanism of course, is also notification to the machine operator that an obstruction of predetermined force application is lodged in the buckets.

It will be seen, therefore, that without any actuation of the directional control valve 78 whatsoever, there is provided a means for effectively protecting the cleaning mechanism against obstructions, etc. in the buckets, which could materially damage such mechanism. Also, by changing the settings of the relief valve sections to suit a variety of digging conditions as encountered throughout the world, this automatic trip can be adjusted so as to accommodate very sticky types of soil or any other types of soils that may be found during digging operations by the machine. It will be seen that relief section 85 is of the prime importance in the system illustrated, since it unloads the piston rod side of the motor unit. It will be understood, therefore, that relief section 84 could be eliminated so far as obtaining the desired automatic trip from active position of the cleaner mechanism illusstrated is concerned. Relief section 84 does however protect the system during powered retraction of the cleaning mechanism by the machine operator.

From the fore-going discussion and accompanying drawings it will be seen that the invention provides a novel bucket cleaning mechanism for an excavating machine,

and especially a novel fluid powered cleaning mechanism for rapidly and easily extending the cleaning mechanism into and out of operative position and in a manner to greatly expedite the digging operation of the buckets of the machine, together with a novel system for controlling the cleaning device of the invention and in a manner insuring that obstructions which may occasionally occur in the buckets, will not damage the cleaning mechanism, but instead the system will automatically permit retraction of the cleaning mechanism :a sufficient amount to permit the obstruction to by-pass the cleaning mechanism.

The terms and expressions which have been used are used as terms of description and not of limitation, and there is no intention in the use of such terms and expressions of excluding any equivalents of any of the features shown or described, or portions thereof, and it is recognized that various modifications are possible within the scope of the invention claimed.

We claim:

1. In an excavating machine comprising a generally horizontally extending support, a digging unit rotatably mounted on said support, buckets mounted on the periphery of said digging unit, and a bucket cleaner mechanism mounted on said support and movable from an inactive position to an active bucket cleaning position and vice versa, said bucket cleaner mechanism comprising an a-rcuate shaped, in side elevation, finger assembly, rail means on said support, means movably coupling said arcuate shaped finger assembly to said rail means, and reciprocable fluid powered means coacting between said support and said finger assembly for moving said bucket cleaner from said inactive to said active position and vice versa, said arcuate shaped finger assembly comprising a base section movably coupled to said rail means and a comb section detachably secured to said base section and extending upwardly therefrom.

2. An excavating machine in accordance with claim 1 wherein said base section includes a pair of depending arms, said fluid powered means being pivotally coupled to said arms adjacent the distal ends thereof and extending between said arms and a pivotal coupling on said support.

3. An excavating machine in accordance with claim 2 wherein said base section is movably coupled to said rail means at two spaced locations thereon, the lengthwise axis of said fluid powered means being disposed between said spaced locations throughout the nange of movement of said bucket cleaner mechanism.

4. An excavating machine in accordance with claim 1 wherein said comb section includes a plurality of leterally spaced, generally arcuate shaped in side elevation fingers, each of said fingers having an abutment spaced inwardly from the tip end thereof, for facilitating the scraping of soil from the buckets by the bucket cleaner mechanism.

5. A bucket cleaner for an excavating machine comprising a support, a scraper movably mounted on the support, said scraper comprising a base section and a comb section having :a plurality of laterally spaced fingers, means detachably connecting said comb section to said base section, fluid powered reciprocal motor means coacting between said support and said scraper for selectively moving the latter from an inactive to an active position and vice versa and a fluid control system comprising automatic fluid actuated means for actuating said motor means to cause withdrawal of the bucket cleaner from a bucket in the event that an obstruction is located in the bucket and engages [the bucket cleaner.

6. A bucket cleaner in accordance with claim 5, wherein said automatic fluid actuated means comprises a relief valve, and fluid transmission means connecting one side of the motor means to the other side thereof via said relief valve.

7. In combination, a movable bucket cleaner for an excavating machine, a reciprocal double acting motor unit including a piston, for moving said bucket cleaner from an inactive position to an active position and vice versa, and a fluid control system "for controlling the actuation of said motor unit, said system comprising a source of pressurized fluid including a reservoir, a directional control valve interconnecting said source and said motor unit for selectively controlling the direction of actuation of said motor unit, and fluid actuated trip means coacting between opposite sides of the piston of said motor unit for transmitting pressurized fluid from one side to the other side thereof when the pressure in said one side exceeds a prede ermined maximum.

8. The combination in accordance with claim 7 including a by-pass line extending between said reservoir and said other side of said piston and bypassing said directional control valve, and check-valve means in said bypass line for permitting flow of fluid in a direction only from said reservoir to said other side.

9. The combination in accordance with claim 7 wherein said fluid actuated trip means comprises a pair of adjustable, fluid actuated relief valves, one of said relief valves being operative to open at a predetermined pressure in one direction of actuation of said motor unit, and the other of said relief valves being operative to open at a predetermined pressure in the other direction of actuation of said motor unit.

It). In an excavating machine comprising a generally horizontally extending support, a digging unit rotatably mounted on said support, buckets mounted on the periphery of said digging unit, and a bucket cleaner mechanism mounted on said support and movable from an inactive position to an active bucket cleaning position and vice versa, said bucket cleaner mechanism comprising an armate shaped, in side elevation, fingers assembly, r-ail means on said support, means movably coupling said arcuate shaped finger assembly to said rail means, and reciprocable fluid powered means coacting between said support and said finger assembly for moving said bucket cleaner from said inactive to said active position and vice versa, said rail means including a linearly extending rail member to which is movably coupled one end of said finger assembly and an arcuate shaped rail member to which is movably coupled said finger assembly at a point spaced from said coupled end of said finger assembly.

11. A bucket cleaner for an excavating machine comprising a support, a scraper movably mounted on the support, said scraper comprising a base section and a comb section having a plurality of laterally spaced fingers, means detachably connecting said comb section to said base section, the base section comprising elongated depending arm means, fiuid powered reciprocal motor means coacting between said support and said scraper for selectively moving the latter from an inactive to an active position and vice versa and means pivotally mounting said motor means to said arm means.

References Cited by the Examiner UNITED STATES PATENTS 1,244,006 10/1917 Wadsworth 37-97 1,719,328 7/1929 Greirnan 198-144 1,762,492 6/1930 VanScOit 198-144 1,966,597 7/1934 Penote 198-144 2,236,467 3/1941 Clench 60-52 2,251,487 8/1941 H-osmer 37-142 2,406,826 9/1946 French et a1 37-129 2,730,821 1/1956 Fetzner 37-97 ABRAHAM G. STONE, Prima'ry Exmniner.

BENJAMIN HERSH, WILLIAM A. SMITH III,

Examiners.

W. B. STONE, Assistant Examiner. 

1. IN AN EXCAVATING MACHINE COMPRISING A GENERALLY HORIZONTALLY EXTENDING SUPPORT, A DIGGING UNIT ROTATABLY MOUNTED ON SAID SUPPORT, BUCKETS MOUNTED ON THE PERIPHERY OF SAID DIGGING UNIT, AND A BUCKET CLEANER MECHANISM MOUNTED ON SAID SUPPORT AND MOVABLE FROM AN INACTIVE POSITION TO AN ACTIVE BUCKET CLEANING POSITION AND VICE VERSA, SAID BUCKET CLEANER MECHANISM COMPRISING AN ARCUATE SHAPED, IN SIDE ELEVATION, FINGER ASSEMBLY, RAIL MEANS ON SAID SUPPORT, MEANS MOVABLY COUPLING SAID ARCUATE SHAPED FINGER ASSEMBLY TO SAID RAIL MEANS, AND RECIPROCABLE FLUID POWERED MEANS COACTING BETWEEN SAID SUPPORT AND SAID FINGER ASSEMBLY FOR MOVING SAID BUCKET CLEANER FROM SAID INACTIVE TO SAID ACTIVE POSITION AND 